It's now possible to specify the threshold time for perf.data like: $ perf record --switch-output=30s ...
Once it's reached, the current data are dumped in to the perf.data.<timestamp> file and session does on. $ perf record --switch-output=30s ... [ perf record: dump data: Woken up 44 times ] [ perf record: Dump perf.data.2017010213043746 ] ... The time is expected to be a number with appended unit character - s/m/h/d. Signed-off-by: Jiri Olsa <jo...@kernel.org> Cc: David Ahern <dsah...@gmail.com> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Cc: Wang Nan <wangn...@huawei.com> Link: http://lkml.kernel.org/n/tip-2u6y3h89c0guejpn1nwv3...@git.kernel.org --- tools/perf/Documentation/perf-record.txt | 2 ++ tools/perf/builtin-record.c | 44 ++++++++++++++++++++++++++++++-- 2 files changed, 44 insertions(+), 2 deletions(-) diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index d838354df417..176f85e89eaa 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -427,6 +427,8 @@ based on 'mode' value: "signal" - when receiving a SIGUSR2 (default value) or <size> - when reaching the size threshold, size is expected to be a number with appended unit character - B/K/M/G + <time> - when reaching the time threshold, size is expected to + be a number with appended unit character - s/m/h/d A possible use case is to, given an external event, slice the perf.data file that gets then processed, possibly via a perf script, to decide if that diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 42321a0fa80e..972272efba47 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -50,6 +50,7 @@ struct switch_output { bool enabled; bool signal; unsigned long size; + unsigned long time; const char *str; bool set; }; @@ -91,6 +92,12 @@ static bool switch_output_size(struct record *rec) (rec->bytes_written >= rec->switch_output.size); } +static bool switch_output_time(struct record *rec) +{ + return rec->switch_output.time && + trigger_is_ready(&switch_output_trigger); +} + static int record__write(struct record *rec, void *bf, size_t size) { if (perf_data_file__write(rec->session->file, bf, size) < 0) { @@ -737,6 +744,7 @@ static void workload_exec_failed_signal(int signo __maybe_unused, } static void snapshot_sig_handler(int sig); +static void alarm_sig_handler(int sig); int __weak perf_event__synth_time_conv(const struct perf_event_mmap_page *pc __maybe_unused, @@ -1068,6 +1076,10 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) err = fd; goto out_child; } + + /* re-arm the alarm */ + if (rec->switch_output.time) + alarm(rec->switch_output.time); } if (hits == rec->samples) { @@ -1387,6 +1399,13 @@ static int switch_output_setup(struct switch_output *s) { .tag = 'G', .mult = 1 << 30 }, { .tag = 0 }, }; + static struct parse_tag tags_time[] = { + { .tag = 's', .mult = 1 }, + { .tag = 'm', .mult = 60 }, + { .tag = 'h', .mult = 60*60 }, + { .tag = 'd', .mult = 60*60*24 }, + { .tag = 0 }, + }; if (!strcmp(s->str, "signal")) { s->signal = true; @@ -1401,6 +1420,14 @@ static int switch_output_setup(struct switch_output *s) goto enabled; } + val = parse_tag_value(s->str, tags_time); + if (val != (unsigned long) -1) { + s->time = val; + pr_debug("switch-output with %s time threshold (%lu seconds)\n", + s->str, s->time); + goto enabled; + } + return -1; enabled: @@ -1576,8 +1603,8 @@ static struct option __record_options[] = { OPT_BOOLEAN(0, "timestamp-filename", &record.timestamp_filename, "append timestamp to output filename"), OPT_STRING_OPTARG_SET(0, "switch-output", &record.switch_output.str, - &record.switch_output.set, "signal,size", - "Switch output when receive SIGUSR2 or cross size threshold", + &record.switch_output.set, "signal,size,time", + "Switch output when receive SIGUSR2 or cross size,time threshold", "signal"), OPT_BOOLEAN(0, "dry-run", &dry_run, "Parse options then exit"), @@ -1645,6 +1672,11 @@ int cmd_record(int argc, const char **argv, const char *prefix __maybe_unused) if (rec->switch_output.enabled) rec->timestamp_filename = true; + if (rec->switch_output.time) { + signal(SIGALRM, alarm_sig_handler); + alarm(rec->switch_output.time); + } + if (!rec->itr) { rec->itr = auxtrace_record__init(rec->evlist, &err); if (err) @@ -1797,3 +1829,11 @@ static void snapshot_sig_handler(int sig __maybe_unused) if (switch_output_signal(rec)) trigger_hit(&switch_output_trigger); } + +static void alarm_sig_handler(int sig __maybe_unused) +{ + struct record *rec = &record; + + if (switch_output_time(rec)) + trigger_hit(&switch_output_trigger); +} -- 2.7.4
